Ion Gripscrew Thread Size

[Panthro]

Well if you don't want to buy a tap from above link (providing the link work)

A no.6 unc is just over 3.5mm in diameter, the next size up a 4 will not work as it will be too slack,

Drill and tap for a 5 mm Yes but forgive for i have sinned, I have re-consulted with the gods and 5/16" is just over 7.9mm not 8. So just be careful with the length as you stand chance of screwing your solenoid.

 

[Marcus Geezer]

Panthro thank you, you have been very helpful.

I think just to be 100% sure I'm gonna look up a small local engineering firm, have a chat with them about what I'm trying to do, let them do it and let them supply suitable length screws as well, hopefully 1mm shorter than standard just to be sure.

Should be able to get them to do it for the price of a pint or two.

Thanks to everyone who posted.